Intra- and interobserver concordance of a new classification system for myopic maculopathy.

BACKGROUND: Myopic maculopathy (MM) is one of the major causes of visual impairment and irreversible blindness in eyes with pathologic myopia (PM). However, the classification of each type of lesion associated with MM has not been determined. Recently, a new MM classification system, known as the ATN grading and classification system, was proposed; it is based on the fundus photographs and optical coherence tomography (OCT) images and includes three variable components: atrophy (A), traction (T), and neovascularization (N). This study aimed to perform an independent evaluation of interobserver and intraobserver agreement for the recently developed ATN grading system for MM. METHODS: This was a retrospective study. Fundus photographs and OCT images of 125 patients (226 eyes) with various MMs were evaluated and classified using the ATN grading of the new MM classification system by four blinded and independent evaluators (2 attending ophthalmologists and 2 ophthalmic residents). All cases were randomly re-evaluated by the same observers after an interval of 6 weeks. The kappa coefficient (κ) and 95% confidence interval (CI) were used to determine the interobserver and intraobserver agreement. RESULTS: The interobserver agreement was substantial when considering the maculopathy type (A, T, and N). The weighted Fleiss κ values for each MM type (A, T, and N) were 0.651 (95% CI: 0.602-0.700), 0.734 (95% CI: 0.689-0.779), and 0.702 (95% CI: 0.649-0.755), respectively. The interobserver agreement when considering the subtypes was good or excellent, except for stages A1, A2, and N1, in which the weighted κ value was less than 0.6, with moderate agreement. The intraobserver agreement of types and subtypes was excellent, with κ > 0.8. No significant differences were observed between the attending ophthalmologists and residents for interobserver reliability or intraobserver reproducibility. CONCLUSIONS: The ATN classification allows an adequate agreement among ophthalmologists with different qualifications and by the same observer on separate occasions. Future prospective studies should further evaluate whether this classification can be better implemented in clinical decision-making and disease progression assessments.

[Population-based survey of refractive error in school-aged children in Liwan District, Guangzhou].

OBJECTIVE: To estimate the prevalence of refractive error in school-aged children in urban setting of Southern China. METHODS: In this population-based cross-sectional study, children aged 5 to 15 years old were randomly selected by clustering sampling and door-to-door survey, and were examined in 71 schools and 19 community stations from October 2002 to January 2003. The examination included visual acuity measurement, ocular motility evaluation, retinoscopy, autorefraction under cycloplegia and examination of the external eye, anterior segment, media, and fundus. RESULTS: Of 5053 children living in 4814 households enumerated, 4364 (86.4%) were examined. The prevalence of myopia (spherical equivalent, SE < -0.50 D) was 35.1% (95% CI: 33.2%-36.9%) with retinoscopy, this rate increased from 3. 3% in 5-year-old to 73.1% in 15-year-old. Females had a significantly higher risk of myopia (adjusted odds ratio: 1.29, 95% CI: 1.11-1.51). The prevalence of hyperopia (SE > or = + 2.00 D) was 5.8% (95% CI: 5.3%-6.3%) and decreased from 16.7% in 5-year-old to less than 1% in 15-year-old. Astigmatism (cylinder > or = 0.75 D) was presented in 33.6% of children examined with retinoscopy and in 42.7% with autorefraction. CONCLUSIONS: The prevalence of myopia is high in Chinese school-age children living in urban Guangzhou, representing an important public health problem. The coverage and quality of refractive correction in the children need to be improved.